Re: Fast 64-bit atomic writes (SSE?)

[Andi Kleen]

Roland Dreier <roland@xxxxxxxxxxxxxxxxxx> writes:
> 
> General question:
>   What's the best way to do this?

Definitely not how you do it ;-) You corrupt the user space FPU context.
Also you didn't do a CPUID check, so it would just crash on machines

The RAID code has some examples on how to use SSE2 in the kernel correctly.

Better is probably to use CMPXCHG8, which avoids all of this.  

-Andi
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